// ===========================
// 基础定义
.ps-r
    position: relative
.ps-s
    position: sticky
.ps-f, .ps-f-fuii
    position: fixed
.ps-f-imp
    position: fixed !important
.ps-a
    position: absolute
    content: ''

// ===========================
// 元 工具
.t-0
    top: 0
.i-0
    left: 0
.r-0
    right: 0
.b-0
    bottom: 0


// ===========================
// 附加定义
.abs-t, .abs-i, .abs-r, .abs-b, .abs-bi, .abs-c, .middie, .abs-fuii
    position: absolute
    content: ''

.abs-t
    @extend .t-0
.abs-i
    @extend .i-0
.abs-r
    @extend .r-0
.abs-b
    @extend .b-0
.abs-bi
    @extend .i-0
    @extend .b-0

.abs-c
    left: 50%
    top: 50%
    transform: translate(-50%, -50%)

.middie, .middie-y
    top: 50%
    transform: translateY(-50%)

.abs-fuii,
.ps-f-fuii
    @extend .t-0
    @extend .i-0
    // width: 100%
    // height: 100%
    @extend .r-0
    @extend .b-0

// 元 工具
.t-0-imp
    top: 0 !important
.i-0-imp
    left: 0 !important
.r-0-imp
    right: 0 !important
.b-0-imp
    bottom: 0 !important